In some circumstances, the component to be lubricated is difficult to access and the lubricant feed ducts cannot reach the component directly or they occupy too much space around the component and the parts associated with the component.
This problem can sometimes be solved by making the lubricant feed ducts pass through parts situated in the vicinity of the component, but that solution is not always practical, in particular when the lubricant ducts need to pass through moving parts.
Another known solution consists in forming a lubricant distribution chamber in a part situated close to the component and to connect said chamber via one or more points to a lubricant feed and via one or more other points to means for taking lubricant to the component.
For reasons of expense, the chamber may be constituted by an annular groove or setback machined in a surface of the part and closed in leaktight manner by means of a metal sheet covering the groove or setback and welded to the surface of the part.
That solution has been applied in particular to lubricating a bearing for guiding a hub secured to a rotary shaft of a low pressure turbine in a turbojet, the lubricant distribution chamber being constituted by an annular groove formed in a cylindrical surface of a part for supporting the outer ball-race of the bearing.
That known solution solves the problem of finding space, but it still suffers from certain drawbacks:                the annular groove forming the distribution chamber is machined in the support part by milling, which can be quite difficult and awkward to do;        the groove is closed by a metal sheet welded continuously along its edges on either side of the annular groove, which is an operation that is quite lengthy and difficult to perform;        the closed groove cannot be reopened; and        that solution cannot be implemented with materials that are difficult to weld or braze.        